Fire alarm

ABSTRACT

An audible alarm system for Yukon stoves or the like including a box-type body member containing an audible alarm with an actuating means, such as, a gas-operated whistle or horn, a puncturable, pressurized CO2 bottle, puncturing means for the bottle and a tension spring adapted to forceably swing the puncturing means into puncturing position or a bell with a resiliently mounted striker adapted to vibrate against the sounder of the bell, mounting means, such as, a magnet, for attaching the body member to the side of the stove, a support mounted in the body member having a mast extending upwardly to a predetermined height above the top of the stove and an arm extending across the top of the stove and a flexible sensor, such as, a wire-type fuse resistant to heat but actuatable by contact with a flame, extending along the arm of the support, thence down the mast of the support and connected to the releasable alarm so as to hold the actuating means in a cocked position and to release the actuating means when the fuse burns.

United States Patent 1191 Dunn [451 Aug. 26, 1975 FIRE ALARM 22 Filed: May 23,1973

211 Appl.No.:363,261

[52] US. Cl. 116/104 [51] Int. Cl. G08b 17/02 [58] Field of Search 116/2, 5, 101, 104, 112, 116/106; 126/38, 43

[56] References Cited UNITED STATES PATENTS 424,545 4/1890 Earl 116/104 679,176 7/1901 Linden 116/104 804,357 ll/1905 Watkins 116/106 2,569,062 9/1951 Kjcldcrgaard... 1. 116/106 2,626,586 l/1953 Mcndes 116/106 2,769,422 11/1956 Jcnks 116/101 3,145.704 8/1964 Brocckcr l 126/38 3,391.36? 7/1968 Messick 116/101 X FOREIGN PATENTS OR APPLICATIONS 20,698 1/1883 Germany 116/104 Primary Examiner-S. Clement Swisher Assistant Examiner-Denis E. Corr Attorney, Agent, or Firm-Charles F. Steininger 5 7 ABSTRACT An audible alarm system for Yukon stoves or the like including a box-type body member containing an audible alarm with an actuating means, such as, a gasoperated whistle or horn, a puncturable, pressurized CO bottle, puncturing means for the bottle and a tension spring adapted to forceably swing the puncturing means into puncturing position or a bell with a resiliently mounted striker adapted to vibrate against the sounder of the bell, mounting means, such as, a magnet, for attaching the body member to the side of the stove, a support mounted in the body member having a mast extending upwardly to a predetermined height above the top of the stove and an arm extending across the top of the stove and a flexible sensor, such as, a wire-type fuse resistant to heat but actuatable by contact with a flame, extending along the arm of the support, thence down the mast of the support and connected to the releasable alarm so as to hold the actuating means in a cooked position and to release the actuating means when the fuse burns.

8 Claims, 9 Drawing Figures SHEET 1 UF 3 PATENTEU AUGZBlQTS PATENTED AUG 2 6 I975 SHEET 2 BF 3 PATENTED 1418261915 3, 90 1 179 SHEET 3 n5 3 FIGQ FIRE ALARM BACKGROUND OF THE INVENTION The present invention relates to a fire alarm system. More particularly, the present invention relates to a fire alarm system detachably mountable on a stove.

In the prior art, there are a large number of fire alarms which automatically give an audible signal should a fire be detected in the spot or area to be protected. These systems fall into one of two general catagories, namely; those which are of the permanent installation type and are designed to cover a large area and those which are considered portable and are designed to respond only at a particular point of use.

There are a wide variety of alarms which can be considered to be of the permanent installation type and thereby cover or detect the presence of a fire in a large area which is to be protected. In this catagory, the alarm as such is generally located ata particular spot in the room or other area to be protected and the area to be protected is covered by wire stretched under tension across the area to be protected. When the wire melts, it releases the tension on the wire and thereby releases a mechanical alarm or a gas-operated alarm. In most cases, the wire is a fusible wire which melts at a predetermined temperature and thereby sets off the alarm. Alarm systems of this type are obviously useless where the detection area is normally subject to high heat such as adjacent a stove or the like. While some few of the prior art devices of the permanent installation type do use wires or fuses which burn on contact with a flame, the manner of installation of the burnable wire fuse prevents the alarm from being actuated unless a rather large conflagration exists. At such time, it is usually too late to do anything about the detected fire. More importantly, however, systems of this type are expensive to install and maintain, require expert installation, are rather delicate, and certainly cannot be considered portable of disposable In the other catagory of alarm systems, where the alarm is designed to detect a fire at a single location, the alarm system may be considered portable to some extent, thus overcoming one of the problems of the permanent installation type. However, such systems also have numerous disadvantages. Generally, they are constructed with a fusible plug or link which melts at a predetermined temperature, thereby releasing a me chanical alarm or releasing a gas which, in turn, actuates an acoustic signal of some type, such as, a horn or the like. Obviously, with a fusible plug or fusible link, the system will detect a fire in the general area of its location but it cannot be utilized where it will be subjected to normally high heat, such as, adjacent a stove. While such systems may be classifiedgenerally as portable, they are usually sufficiently complex that they are not disposable after a single actuation. These systems are also sufficiently complex that they lack ruggedness, which is required in certain areas where such an alarm is desired.

From the above summary of the prior art, it is quite obvious that all of the prior art systems have one or more drawbacks which prevent their use in certain areas and under certain conditions where a definite need exists. One such problem area is in the detection of a fire adjacent a camp stove or heater. For example, in remote army installations or in forward combat ar eas, large tents are set up which generally house ten men. In order to cook and supply heat in such quarters, a Yukon stove is utilized. This stove is a portable device resting on collapsible legs, having one or more burners and having a chimney stack or flue on one end thereof. Fuel is supplied to the stove through a flexible hose from a five-gallon Gerry can. The Gerry can is normally placed in a location higher than the stove so as to feed gasoline, oil, diesel fuel, etc. by gravity to the stove. Presently, there is no means of detecting when the Yukon stove might flare up or produce a flame higher than normal and thus providing a warning before the shelter becomes engulfed in flames. Obviously, such a system would have to be actuated in sufficient time to permit evacuation of the shelter or the taking of some action to cut off the Yukon stove. Obviously too, in Arctic areas where the stove is used for heat, it is necessary to awaken the sleeping occupants of the shelter. While the answer to this problem is to provide an alarm system ofsome kind, the conditions and manner of use place very stringent requirements on such a system. For example, the system must be rugged so that it can be employed in remote locations and forward combat areas and also be capable of being air-dropped along with other logistic supplies. The system must also be extremely simple in construction and simple to install. The system must also be serviceable at extremely low temperatures, such as, in Arctic regions and where high continuous temperatures are normally emitted from the side of the stove. Most desirable, also, is that the system be designed to be disposable after a single actuation. Certainly, any system meeting the abovementioned stringent requirements would also be useful in conjunction with portable stoves, heaters and the like utilized in civilian camping. These and other objects and advantages of the present invention will be apparent from the following description.

SUMMARY OF THE INVENTION Briefly, in accordance with the present invention, an audible fire alarm, for detecting a fire above an object, such as,a Yukon stove or the like, is provided, comprising; a body member containing an audible alarm means and alarm actuating means operably associated with the alarm, means for releasable attaching the body member to the object, a generally-L-shaped support including an upstanding mast attached to the body member and of a length-sufficient to extend a predetermined distance above the top of the object and a horizontallydisposed arm extending across the top of the object, and a flexible sensor resistant to heat but flammable when contacted by a flame, extending along the length of the arm and thence down the mast and connected to the actuating means to hold the same in a cocked position and to release the actuating means when the sensor burns.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 of the drawings shows the alarm system in use on a Yukon stove;

FIG. 2 is a side view, partially in section, of one embodiment of the alarm system;

FIG. 3 is a top view, partially in section, of the puncturing assembly of FIG. 2;

FIG. 4 is a front view, partially in section, of the clamp of FIG. 3;

FIG. 5 is a front view of a second embodiment of a mounting means for the alarm system;

FIG. 6 is a top view, partially in section, of another embodiment of the sensor support for the alarm system;

FIG. 7 is a side view, partially in section, of the support of FIG. 6;

FIG. 8 is a side view of another embodiment of a sensor support for the alarm system; and

FIG. 9 is a side view, partially in section, of an alternate alarm and actuator means for the alarm system.

DETAILED DESCRIPTION OF THE INVENTKON In accordance with FIG. 1 or" the drawings, the numeral it) represents a Yukon stove. Stove 10 is provided with foldable legs 12 and detachable chimney or flue stack 14. Door 16 is provided in one end of the stove 10 for access, and mounted through the top of stove 16 is a burner 18. Fuel is supplied to stove 10 from can 20. Can 20 is usually a S-gallon Gerry can containing gasoline, diesel oil, etc. Fuel from can 20 is fed to shye 10 by gravity through flexible hose 22. Detachably mounted on the side of stove 10 is audible alarm system 24. Audible alarm system 24 comprises body member 26 and sensor support bracket means 28. Support 28 is made up of vertically-disposed mast 30 and horizontally-disposed arm 32 which projects across and above burner 18 of stove 10. Arm 32 is foldable or collapsible upwardly against mast 30 by means of a hinged joint (not shown) and it is held in the horizontal position by flexible wire 34. A flexible sensor 36 is wound about arm 32 and the lower portion of mast 30 and leads to the body 26 of alarm system 24.

FIG. 2 of the drawings shows in greater detail one embodiment of the audible alarm system 24 of the present invention. Body member 26 of alarm system 24 includes back wall 38, front wall 40, top 42, bottom 44 and side walls 46, one of which has been removed to show the interior of the body of the alarm. Body 26 is divided into an upper chamber 48 and a lower chamber 50 by horizontally-disposed divider 52. Mounted on the back 38 is magnet 54 which is utilized to attach the alarm system to a stove or other item where an uncontrolled fire is to be detected. The support 28 is, of course, made up of mast 30 and horizontal arm 32 and has wound thereabout sensor 36. For ease of packaging and assembly, a generally-U-shaped channel 56 is mounted on wall 46 to receive mast 30 is slidable engagement. Channel 56 may also be a tubular receptacle fixedly mounted on the wall 46 to receive mast 30. Arm 32 is fixedly attached to mast 30 by generally-C-shaped channel 58, which has a cutout portion which conforms to the contour of mast 30 and is pivotally attached to mast 30 through pivot 60. For shipping or storage, arm 32 will pivot upwardly about pivot 60 and lock in place by means of coacting convex button 62 on mast 30 and concave depression 64 in channel 58. Mounted in upper chamber 48 is pressurized gas bottle 66. Pressurized gas bottle 66 is preferably a pressurized and sealed bottle of CO Specifically, an 8 gram bottle such as that used in a Mae Vi/est life jacket having the military designation Mil C 601 B is utilized. Gas bottle 66 is mounted on top of 42 by means of bracket 68. The seal in the top of gas bottle 68 is punctured at the appropriate time by means of pivotal striker 70 carrying puncturing pin 72. Striker arm 70 is pivoted on bracket 74 by means of pivot 76. As will be described in more detail hereinafter, a short length of sensor 78 is attached to and holds striker 70 in the horizontal, cocked position as shown in full lines in the drawing and then passes out an aperture in the top 42. Section 78 of the sensor is then wound or otherwise attached to section 36 of the sensor. When the sensor wire 36-70 burns, thereby releasing striker to permit it to pivot to the vertical position as shown in dashed lines in the Figure, the aperture through which section 78 of the sensor passes is closed by a flapper valve, such as, a rubber disc 80 attached to the top 42. FIGS. 3 and 4 of the drawings shows the mounting and cocking mechanism for striker arm 70. As previously indicated, striker arm 70 is pivotally mounted on support 74 by means of pivot 76 passing therethrough, A helical spring 82 has one end thereof mounted in bracket 74 and the other end thereof pressed against the top of striker arm 70, and is, of course, under tension. In order to cock the striker arm in the horizontal position, spring clip 84 is mounted in apertures in the side walls of bracket 74. The striker arm 70 is then raised to the horizontal position and clamped between the mid portions of spring clip 84. The section 78 of the sensor is then wrapped around the free ends of spring clip 84 in order to hold striker arm 70 in the horizontal position. FIG. 4 of the drawings shows the spring clip 84 with the striker arm held between its midportion and the sensor 78 wound thereabout.

In the operation of the system as shown in FIGS. 2, 3 and 4, the body assembly of the system is preassembled to the extent that all elements are assembled in the body portion 26, the striker arm 70 is cooked and the sensor portion 78 is attached and passes through the top 42. The mast 30 is then inserted in the channel 56, arm 32 is moved downwardly to the horizontal position, and portion 36 of the sensor is then wound around the arm 32, thence downwardly about mast 30 and is then attached to section 78 of the sensor, as by twisting the two together or in some other way. The magnet is then attached to the side of a stove, such as, stove 10 of FIG. 1, with the arm 30 carrying sensor 36 extending over the burner of the stove. To the extent that the flame of the stove reaches an undesirable height and contacts the sensor wire 36, the wire burns rapidly releasing the tension on clip 84 which, in turn, releases striker arm 70. Striker arm 70 then moves to the vertical position and punctures the seal in gas bottle 66. The gas released from bottle 66 passes through aperture 86 in divider 52, which may be covered by a frangible disc 88 which fractures at a predetermined pressure, and pressurizes lower chamber 46. The pressure in lower chamber 46 then actuates a horn or whistle 96.

FIG. 5 of the drawings shows an alternate means for attaching the alarm system 24 to a stove or the like. In accordance with FIG. 5, a generally-V-shaped receiving plate 92 is attached to the stove or the like by means of self-tapping screws 94. Receiving clamp 92 has its side edges turned over to form flanges 96 and thereby form generally-U-shaped channels along the edges of the receiving plate 92. Attached to the back of the body portion 26 of alarm system 24 is a generally-V-shaped plate 98 which is adapted to slide downwardly and be held in the channels formed by flanges 96 of receiving plate 92. Plate 98 is attached to the back 38 of body member 26 by welding or other means through projecting spacer block 100.

F105. 6 and 7 of the drawings show another modification of the support means 28 for the sensor 36. In accordance with FllGS. 6 and 7, the sensor support 28 is made up of mast 102 and arm 104. Mast 102 is appropriately cylindrical in structure while arm 104 is a generally-C-shaped channel. Channel 104 has formed therein a cut out 106 which conforms to the contour of mast 102, thereby acting as a stop when the arm 104 is swung down to a horizontal position. Arm 104 is pivoted on mast 102 by means of pivot 108. Thus, the arm 104 may be pivoted to the vertical position for storage or transport or pivoted downwardly to the horizontal position for use on a stove, and there is no need for a support, such as, wire 34 of FIG. 1, to hold arm 104 in its horizontal position. The sensor 36 may be either wound about the arm 104 and mast 102, as in FIG. 2, or it may be partially wound and passed through aperture 1 in arm 104, then across the bottom of arm 104 and thence upwardly through aperture 112 in arm 104. Thereafter, sensor 36 is either wound about or led down the side of mast 102. The sensor 36 may also pass through an aperture in mast 102 if desired.

FIG. 8 of the drawings shows still another form of the sensor support 28 in accordance with the present invention. In accordance with FIG. 8, sensor support 28 is made up of vertical mast 1 14 and horizontal arm 116. Both arm 116 and mast 114 are adapted to telescope by means of at least two telescoping sections. Arm 116 is attached to mast 114 by means of generally-U- shaped bracket 118. Bracket 118 is fixedly attached to arm 116 and pivotally attached to mast 114 by means of pivot 120. Thus, arm 116 may be pivoted downwardly parallel to mast 114 for packaging or shipping. Channel 118 is provided at its upper edge with an L shaped, spring-type clamp 122. Clamp 122 passes over the top of mast 114 and has a projecting portion which fits into a depression 124 in the side of mast 114 to thereby lock arm 116 in the horizontal position. It is obvious from FIG. 8 that the sensor support 28 may be folded and telescoped to a length which is little longer than one of the telescoping sections of the arm 116 and/or the mast 114. This obviously facilitates packaging and shipment of the alarm system.

FIG. 9 of the drawings shows an alternate acoustic signal means which does not utilize gas pressure but instead is mechanical in operation. Specifically, in accordance with FIG. 9 of the drawings, a sounder 126 of conventional bell is mounted on side wall 46 of the body member 26. A striker 128 is mounted on the top wall 42, through flat spring support 130. Flat spring support 130 has sufficient resilience that once released from a cocked position or a position of initial stress, it will continue to vibrate for a reasonable length and thereby give a signalv This vibration may, if desired, be aided by helical, compression spring 132, attached to front wall 40. Spring 130 may be used alone or in combination with spring 132. The spring -l32 could be attached to spring 130 and thence to the top 42 rather than having a free end positioned opposite striker 128. In this particular instance, in order to set the alarm, section 78 of the sensor is wound about or otherwise attached to spring 130 of striker 128, then passes upwardly through an aperture in top 42 and is'anchored by passing it through and/or winding it about post 134 mounted on top 42. In this case, the spring arm 130 could be held in its cocked position by means of a clip, sich as clip 84 of FIG. 4, and sensor lead 78 could be wound about this clip to hold arm 130 in the cocked position. However, the resilience of spring arm 130 is such that such a clip is not absolutely essential and the striker may be held in a cocked position simply by utilizing the winding post 134f-orsome other equivalent securing means. i

The operation of the device of HG. 9 is essentially the same as previously described. The sensor passing across the horizontal arm 1 rapidly burns when it is struck by a flame. This, in turn, releases striker 128 which will vibrate against sounder 126 as a result of the resilience of springs and 132.

The sensor should be selected on the basis of the conditions under which it is to be utilized. The primary requirement is that the sensor should not be spontaneously ignited by heat alone but will be ignited when a flame strikes it and will burn rapidly. The sensor may take the form of an organic filament, such as, cotton, rayon, silk, etc., or a synthetic filament, such as, nylon (linear polyamide), orlon (linear polyester), dacron (linear polyacrylonitrile, etc. However, in most instances, such sensors will not burn rapidly enough to satisfy the requirements of use to which the present invention is subjected and they will not have sufficient rigidity. Accordingly, the sensor may be a conventional blasting fuse, such as, cordite, Preferably, however, the blasting or explosive fuse is a wire-type fuse, such as, PYROFUSE, manufactured by Pyrofuse Corporation, Mount Vernon, New York. This fuse wire burns rapidly and has sufficient strength to meet all the requirements of the present invention. In general, this is a braided wire-type fuse having a core of aluminum and an outer shell of platinum or palladium. For the particular use disclosed herein, the Pyrofuse is preferably 4 mils, 8 braid wire.

While specific structures and variations of the same have been shown and described herein for purposes of illustration, it is to be understood that various modifications and equivalents of such structures will be apparent to one skilled in the art. Accordingly, the present invention includes such modifications and equivalents and is to be limited only in accordance with the appended claims.

I claim:

1. An alarm. system for detecting a fire above an object, comprising; a body member enclosing an audible, gas-operated alarm means and alarm actuating means, including, a source of gas under pressure and release means for releasing said gas under pressure, operably associated with said alarm means to actuate said alarm means; a wire-type sensor means, substantially resistant to ignition by flameless heat alone and ignitable substantially instantaneously when struck by a flame, operatively coupled to said actuating means and extending through and to the outside of said body member to operate said actuating means and actuate said alarm means when said sensor is struck by a flame and burns and means for attaching said body member in the area to be protected to expose said sensor to a flame occurring in said area to be protected.

2. A system in accordance with claim 1 wherein the source of gas under pressure is a container of C0 3. A system in accordance with claim 1 wherein the release means is a means for puncturing a container of gas under pressure.

4. A system in accordance with claim 3 wherein the means for puncturing the container is spring-biased toward the container and the flexible sensor holds said means for puncturing said container away from said container.

a magnet.

7. A system in accordance with claim 1 wherein the L-shaped support is collapsible to a generallyelongated configuration.

8. A system in accordance with claim 1 wherein the sensor comprises metallic aluminum in intimate association with a metal selected from the group consisting of platinum and palladium. 

1. An alarm system for detecting a fire above an object, comprising; a body member enclosing an audible, gas-operated alarm means and alarm actuating means, including, a source of gas under pressure and release means for releasing said gas under pressure, operably associated with said alarm means to actuate said alarm means; a wire-type sensor means, substantially resistant to ignition by flameless heat alone and ignitable substantially instantaneously when struck by a flame, operatively coupled to said actuating means and extending through and to the outside of said body member to operate said actuating means and actuate said alarm means when said sensor is struck by a flame and burns and means for attaching said body member in the area to be protected to expose said sensor to a flame occurring in said area to be protected.
 2. A system in accordance with claim 1 wherein the source of gas under pressure is a container of CO2.
 3. A system in accordance with claim 1 wherein the release means is a means for puncturing a container of gas under pressure.
 4. A system in accordance with claim 3 wherein the means for puncturing the container is spring-biased toward the container and the flexible sensor holds said means for puncturing said container away from said container.
 5. A system in accordance with claim 1 wherein a generally-L-shaped support means is attached to said body member and a portion thereof extends beyond said body member and the sensor is coupled to said support and extends along said support in a position whereby said sensor is exposed to a flame in the area to be protected.
 6. A system in accordance with claim 5 wherein the means for attaching the body member to the object is a magnet.
 7. A system in accordance with claim 1 wherein the L-shaped support is collapsible to a generally-elongated configuration.
 8. A system in accordance with claim 1 wherein the sensor comprises metallic aluminum in intimate association with a metal selected from the group consisting of platinum and palladium. 